A blog about everything and anything...but mostly science, philosophy and other stuff

Friday, July 31, 2015

We're not moving to Earth 2.0 any time soon

There has been a great furore about a new Earth (dubbed Earth 2.0) deep
in outer space. People are excited about this scientific discovery but
for all the wrong reasons.

Are we moving there soon?

Since
the discovery, I have witnessed many an internet meme discussing the
possibility of moving the human population to this new planet. Some even
entertain the idea of it being a safe haven for when this planet goes
to the dumps.

Our precious planet, this pale blue dot in
the great vastness of the universe is precious to us. It is the only
planet we currently live on, and more importantly, earth is where I keep
all my stuff.

To our best scientific knowledge, planet
earth is the only planet that can sustain life. For a planet to sustain
life as we know it, it needs to pass some important criteria.

The
planet needs to have liquid water which exists inside a very narrow
range of temperature from 0°C to 100°C. A planet too close to its star
will be too hot, a planet to far away from its parent star will be far
too cold.

So a planet at just the right distance from its
star is just right to host life as we know it. No wonder the zone where
such a planet needs to exist is called the Goldilocks Zone for
conditions for life that are "just right".

Like our home
planet, Earth 2.0 is found to be in such a region and other analyses
have found other similarities to our home planet using nothing else but
thousand-four-hundred-year-old light.

Being so far away,
going to the planet is out of the question. So, what is so great about
an earth-like planet that is hopelessly out of our reach?

Well,
it helps us edge closer to answering the question of whether we are
indeed alone in the universe and to understand how this, we need to
understand the process of looking for these planets in our galaxy.

Basics of planet hunting

Looking
for planets in other solar systems isn't easy. No planet outside our
solar system has ever been directly photographed so other means have to
be used to find it.

A small telescope orbiting earth
called the Kepler Space Telescope, looks toward the stars to spot the
shadows of planets orbiting those stars. The task is equivalent to
spotting a fly passing in front of a flood light from a few kilometres
away.

In order to detect the fly, it needs to pass
directly in front of the flood-light so that it is between the lamp and
your line of sight and you need to be somewhat lucky to see it.

We
were lucky enough to find this planet using this method and in order to
understand the significance of this discovery, we need to consider
another analogy.

Imagine you had to find a mango tree in a
forest as the one (earth) you are currently at has been depleted of its
fruit. Say, you take a few minutes look for another in the dense forest
and find and another.

You would assume one of two things.
Either you were very lucky to discover the only other mango tree in the
dense forest or you are not so lucky and mango trees are abundant
throughout the forest.

The latter would make better sense
and give you hope in the abundance of more mango trees and therefore
more mangos ripe for the picking.

That is the same idea we
can apply in the search for another earth-like planet. The existence of
this earth cousin increases the likelihood of other planets in the
Goldilocks Zone which also increases the chances of the existence of
life as we know it all over the galaxy.

Moral of this story

It is a good thing that people can get excited about science stories but what people discuss needs to be accurate.